The broad objective of this program project is to develop the scientific foundation for effective teaching and evaluation of individuals whose behavior deficits place them outside the reach of methods that are currently available. The research focus is on school-aged children and on deficits that include poorly developed language atypical attention and/or perception, behavioral inflexibility, and several other related problems. The program project aims to (1) advance scientific understanding of behavioral deficits that may impede learning, and (2) verify our understanding by developing teaching technologies that will eliminate or bypass such deficits-thus making positive learning outcomes more likely. Our research program is strongly directed toward teaching applications. We are particularly interested in communication, functional academics (e.g., work recognition, counting, etc.), and their behavioral prerequisites (e.g., detection of stimulus similarity or difference, attending to relevant aspects of structurally complex stimuli, development and use of appropriate strategies, etc.). By their nature, communication and functional academics are complex activities that have a diverse range of behavioral prerequisites. We consider it essential, therefore, to include and integrate studies of perception, attention, symbolic classification, sequencing, and strategic behavior-all processes that must be considered when designing effective teaching interventions. To accomplish the necessary integration, our project team is interdisciplinary in nature. Methods and theoretical perspectives from behavior analysis, cognitive psychology, psycholinguistics, and vision science are all represented. There is a strong emphasis on making use of advances in microcomputer technology to support rigorous behavior analyses and manage the many variables that must be considered when teaching children who need unusual support in learning. Our program project consists of research, each of which addresses essential aspects of learning. Each project would be construed as basic research in an area of clear clinical/educational relevance. The projects are supported and integrated by research core units, which provide essential services, expand the range of methodologies that may be employed, and/or maximize opportunities for bringing the fruits of the research program to practice.